Multi-section projectile and means for firing the same

ABSTRACT

A plurality of generally disclike elements are unitarily arranged in stacked, face contacting relation within a cartridge. The projectile element edges are formed into a set of teeth or projections for cooperation with similarly dimensioned toothed tracks to produce element rotation for movement along guide grooves extending longitudinally within a gun barrel. As a further aspect, the guide grooves are fanned out a predetermined amount in the region immediately adjacent the muzzle to produce a prescribed element dispersion.

Elnited States Patent Schaffer July 29, 1975 [54] MULTLSECTION PROJECTILE AND 1,302,720 5/1919 Schultz 89/14 R 1,777,519 10/1930 Flowers 42/78 MEANS FOR FIRING THE SAME 2,433,334 12/1947 Birkeland... 102/38 X [75} Inventor: Marvin B. Schaffer, Pacific 2,706,356 4/1955 De Vita l02/38 X Palisades, Calif.

[73] Assignee: R & D Associates, Santa Monica, Primary Examinersamuel Feinberg C lif Assistant Examiner-H. J. Tudor {22] Filed: Nov. 24, 1972 57 ABSTRACT [21] Appl. No.: 309,225

A plurality of generally disclike elements are unitarily arranged in stacked, face contacting relation within a [52] US. Cl 102/38; lO2/92.l Cartridge The projectile element edges are formed [51] hit. Cl. F421) 5/02 into a Set of teeth or projections for Cooperation with [58] held of Search 102/38 92-6; similarly dimensioned toothed tracks to produce ele- 89/l4 R; 42/78 ment rotation for movement along guide grooves extending longitudinally within a gun barrel. As a further [56] References Cned aspect, the guide grooves are fanned out a predeter- UNITED STATES PATENTS mined amount in the region immediately adjacent the 616,721 12/1898 Muthherr 102/38 m zzl to produce a prescribed element dispersion. 694,675 3/1902 Scott 102/38 UX 1,204,282 11/1916 Lake 89/14 R 3 Claims, 6 Drawmg Flgures generally disclike elements unitarily. arranged 1 MULTI-SECTION PROJECTILE AND NEANS FOR FIRING THE SAME FIELD OF THE INVENTION OBJECTS AND SUMMARY It is, therefore, a primary object of this invention to provide an improved multi-part projectile which on firing presents an extended bandlike pattern.

Another object is the provision of a multi-section projectile, the parts of which on firing are each imparted with rotative as well as translational motion improving dynamic stability. 1

A further object is the provision of a multi-part projectile, the parts. of which closely fit within grooves in a gun barrel so that during initial firing stages an effective gas seal is maintained between the projectile and gun barrel. 7 I

A still further object is the provision of gun barrel means for the multi-section projectile described in the above objects in which guiding grooves direct the projectile sections along respective paths producing a wedgelike dispersal pattern at a prescribed distance.

In accordance withthe practice of the present-invention the multi-sectionprojectile includes a plurality of m stacked, face contacting relation within a cartridge. The projectile element edges are formed into a set of teeth orprojections which cooperate with similarly dimensioned toothed tracks for rotative movement along guide grooves extending longitudinally within a gun barrel. The cartridge is located within the .gun chamber with the element stack extending transverse of the barrel and the elementsindividually edge-alignedto the guide grooves. As a further aspect, the guide grooves are fanned out a predetermined amount in the region immediately adjacent the muzzle to produce a prescribed element dispersion.

DESCRIPTION OF THE DRAWINGS I FIG. 1 is a perspective view of a cartridge including the multi-section projectile or bullet of the present invention.

FIG. 2 is a perspective view of one element of the multi-section projectile or bullet of FIG. 1.

FIG. 3 is a sectional, elevational view taken along line 3-3 of the cartridge in FIG. 1.

FIG. 4 is an elevational view in section of the cartridge of FIG. 1 within the gun chamber also depicting movement of a projectile element along the gun barrel.

FIG. 5 is a transverse sectional view taken along line 55 in FIG. 4.

FIG. 6 is a plan, sectional view of the barrel end portion especially adapted for use in propulsion of the multi-section projectile of this invention.

DESCRIPTION OF A PREFERRED EMBODIMENT Turning now to the drawings, and particularly to FIGS. 1 and 3, a cartridge assembly 10 is seen to include a hollow cartridge case 11 having a primer assembly 12 in its closed end wall, a quantity of propellant 13, amulti-section bullet or projectile 14 to be more .fully described, and an end wad 15. The cartridge case 11 can be made of, optionally, brass, steel or aluminum and is of conventional construction other than having a generally rectangular cross-section for accommodating the multi-section projectile. The primer may be any one of a number of different commercially or militarily available primers for small arms. Similarly, the propellant 13 may be selected from any number of known substances, and the wad 15 typically may be made of paraffin wax, or the like.

The multi-section projectile 14 includes a plurality of identical circular disclike elements 16, the peripheries of which are formed into a continuous set of equally spaced teeth 17. The elements have their edge margins beveled to a substantial knife edge 18 as seen best in FIGS. 2 and 5. s

The elements 16 may be constructed of any of the usualgbullet materials, e.g., lead, steel, copper, uranium, tungsten, or any other metal having sufficient strength and rigidity to withstand propulsion. Evaluation tests indicate that depleted uranium is a near opti- -mum material from which to construct elements 16.

Tungsten alloys closely follow with steel next.

In assembly after the propellant is added, the elements 16 are stacked in side by side, face contacting relation and inserted into the open end of the cartridge case 11 with the ,edges facing outwardly. The case is crimped as at l9 tov secure the projectile elements therewithin and to align the element teeth transversely of the case. End wad 15 then closes the outer case opening.

As shown best in FIG. 4, the gun chamber 20 is formed to receive the cartridge 10 in a tight fitting relation. The upperinner surfaces of the barrel 21 includes a first set of longitudinally extending grooves 22 of transverse dimension and mutual spacing identical to that of theelements 16 forming the projectile 14. A second set 23 of similar longitudinal grooves is provided along the lowerinside barrel surface, the grooves of the second set being aligned with and in vertical registry with the grooves 22.

The leading end of the cartridge 10 abuts against a shoulder- 24 defining the beginning of the gun barrel, and also, the beginning of the two sets 22 and 23 of guide grooves. Fora short distance along the lower grooves from the shoulder 24, there are provided toothlike projections 25 of dimensions for cooperative action with the bullet element teeth 17 in a way that will be described.

For satisfactory operation there are also required additional apparatus such as a trigger mechanism, stock or grip, magazine, extraction means and sight, for example. All of these may be of conventional construction and do not form a part of the present invention.

When the cartridge 10 in the chamber 20 is fired, the elements 16 move into the chamber with their upper edges being received in the upper set of grooves 22 (FIG. 4). Also, as the elements 16 leave the cartridge case, rotation is initiated by the crimped portion 19 retarding the elements lower edges. On the elements leaving the cartridge case, the lower element edge teeth engage the projections 25 which continues the rotative motion for each element as it simultaneously moves outwardly along the gun barrel. During such movement along the barrel the grooves 22 and 23 maintain the element upright throughout the barrel length so that they are emitted from the muzzle substantially in a line with their edges facing the target. In addition, since the grooves 22 are 23 are formed to closely match the beveled element edges and teeth a gas seal is achieved enhancing propulsion.

An alternate form of gun barrel is that shown in FIG. 6 which obtains a wider dispersion of the bullet elements than that achieved by the first described embodiment. Thus, whereas in the first barrel form the grooves are straight-line throughout the entire barrel length. in this alternate version the grooves in the region 26 immediately adjacent the muzzle curve away from each other or fan out a slight amount. As the multi-section bullet'reaches the region 26, the propellant gases leak past the elements just before they leave the muzzle. Moreover, since the guide grooves diverge, this effects a dispersal of the elements.

Illustrative of a practical embodiment for use in a hand-held or shoulder-fired weapon, each bullet element 16 comprises a disclike body member 0.25 inches in diameter and 0.025 inches thick with 8l0 teeth. Fifty elements stacked in side-by-side relation form a multi-section bullet 1.25 inches by 0.25 inches. It has been found that vertical dispersion, i.e., measured transversely of the element stack, was approximately 1 foot at a distance of 100 feet down range, or substantially 0.5". Lateral dispersion, on the other hand, at the same distance down range was to 10 feet, or 3 to 6. The disc elements spread out generally uniformly and retain their edge forward orientation during flight. In addition, depending on the initial yaw position, some precession of the spinning elements occurs producing a wedgeshaped pattern which may be considered lethal anywhere within the range of 0-300 feet.

There is provided in accordance with the practice of this invention a multi-section projectile or bullet readily adaptable for firing from a number of different kinds of weapons including hand-held and shoulderfired varieties. The different bullet sections or parts separate on firing to form a wedge-shaped pattern that is lethal for an extended range. Moreover, each of the bullet sections spins in the plane of the direction of movement, whereby it is gyroscopically stabilized with its momentum vector perpendicular to the line of flight.

As a further aspect of the subject invention, a multisection bullet is provided in which the pattern achieved upon dispersal downrange can be controlled by modifying the rate of gyroscopic precession. Thus, the angle of dispersion produced at the muzzle of the barrel (FIG. 6) will in turn produce a certain rate of gyroscopic precession effecting a corresponding pattern change.

Although the bullet elements 16 may be made in a conventional disc of uniform thickness throughout, it is advantageous to bevel the edges as in the described embodiments, not only to produce a gas seal as was described, but also to reduce aerodynamic drag during flight.

What is claimed is:

l. A multi-section bullet and cartridge assembly, comprising:

a cartridge casing including a primer and propellant and having portions thereof defining an opening;

a plurality of flat elements arranged in a face-to-face stack secured within the casing opening with the element edges facing outwardly of the opening; and

said casing portions defining the opening being formed into at least one line of crimp along one side only of the stack and interacting with said ele' ments to impart a spin to said elements in a common direction as said elements leave said casing.

2. A multi-section bullet and easing assembly. comprising:

a casing having portions terminating in an opening;

and

a plurality of bullet sections each clampingly received within said casing opening at one side only such that on firing said bullet sections are each gyroscopically stabilized during flight with the momentum vector of each being substantially'perpendicular to the line of flight and in the same directron.

3. A multi-section bullet and easing assembly, comprising;

-a casing including a primer and propellant and having portions thereof defining an opening;

a plurality of tooth-edged disclike elements of substantially identical geometry stackingly received within said casing opening with the element edges facing outwardly of said casing opening; and

said casing portions defining the opening including at least one crimp line extending along one side of the stack of elements and engaging the toothed edges thereof such that on firing spin is imparted to each element. 

1. A multi-section bullet and cartridge assembly, comprising: a cartridge casing including a primer and propellant and having portions thereof defining an opening; a plurality of flat elements arranged in a face-to-face stack secured within the casing opening with the element edges facing outwardly of the opening; and said casing portions defining the opening being formed into at least one line of crimp along one side only of the stack and interacting with said elements to impart a spin to said elements in a common direction as said elements leave said casing.
 2. A multi-section bullet and casing assembly, comprising: a casing having portions terminating in an opening; and a plurality of bullet sections each clampingly received within said casing opening at one side only such that on firing said bullet sections are each gyroscopically stabilized during flight with the momentum vector of each being substantially perpendicular to the line of flight and in the same direction.
 3. A multi-section bullet and casing assembly, comprising; a casing including a primer and propellant and having portions thereof defining an opening; a plurality of tooth-edged disclike elements of substantially identical geometry stackingly received within said casing opening with the element edges faciNg outwardly of said casing opening; and said casing portions defining the opening including at least one crimp line extending along one side of the stack of elements and engaging the toothed edges thereof such that on firing spin is imparted to each element. 